Yol. 56.] IGNEOUS ROCKS OF COUNTY WATERFORD. 665 



greenish xenolithic felsites forming the greater part of the cliffs, in 

 the shape of a sudden increase in the coarseness of the materials 

 so as to form an agglomerate, about halfway between Kilfarrasy 

 Island and Green Island. It is, moreover, noticeable that some 

 of the lava-flows from vents of this age were all but entirely free 

 from xenoliths, though most of those of such a character are of 

 the nature of dykes or veins of later date. 



An nest own. — The whole of the cliffs around Annestown Eay 

 are composed of the widespread pink and greenish xenolithic 

 felsites, exhibiting the usual characters and possessing no distinct 

 bedding ; but they suddenly come to an end opposite Carricka- 

 durrish Eock at the eastern end of the adjoining Morageeha Strand, 

 being abruptly broken off against a group of felsitic rocks, of a 

 totally different character, surrounding a small vent. 



Before proceeding further, it m ay be convenient to review briefly 

 the distribution and development of the foregoing important type of 

 felsitic rocks. The occurrence of clastic volcanic rocks with pink 

 felsitic fragments is first noticeable at Waterfall Cove opposite 

 Hurahan's Eock. It is the easternmost exposure of this type on 

 the coast, and by the coarseness of the materials at this spot the 

 proximity of a vent is suggested. Several other probable sites of 

 vents ejecting similar materials between this point and Annestown 

 have been described, but the chief exposure of pink felsitic lavas 

 associated with these tuffs and agglomerates is observed near Garrarus, 

 where also greenish felsites belonging to the same period of eruption 

 are developed. It is difficult to say definitely whether the bedding 

 occasionally observable in this group of rocks is real, or only 

 apparent, or superinduced. At any rate, evidence is afforded by 

 the slight local variations in character and development, as the 

 rocks are followed from east to west, that more or less irregularity 

 exists in the succession : indeed it is doubtful whether any definite 

 succession is traceable. The presence of a syncline between 

 Hurahan's Eock and Kilfarrasy seems to be suggested by the dip of 

 the beds, so far as it is shown. It is a remarkable fact that no 

 fragments of the greyish felsites and tuffs near Great Newtown 

 Head have been recognized in this series : that it belongs, neverthe- 

 less, to a later period of volcanic activity appears in the highest 

 degree probable. 



The grey and pale greenish felsites which are well developed in 

 the centre of Garrarus Strand belong to another outburst, and are 

 of quite a different type of rock. Moreover, they are not associated 

 with any fragmental beds, and in no place do they contain any 

 fragments of pink felsite. Their characteristic feature is the in- 

 clusion of large masses and irregular pieces of black slate. Probably 

 belonging to this stage of eruptivity are the vents with greyish felsitic 

 materials near Sheep Island, and the other at the Black Door, 

 Kilfarrasy. As these pipes of felsitic material pierce the pink and 

 greenish xenolithic felsites and tuffs of the other series above 

 described, we have reason to believe that they are of later age. 



